Boiler and water heater system



Jan. 15, 1935. f T. D. cAssERLY 1,988,263

K y BOILER AND WATER HEATER SYSTEM Filed Jan. 30, 1955 2 Sheets-Sheet 1 Jan. 15, 1935. T. D. cAssERLY BOILER AND WATER HEATER SYSTEM Filed Jan. 30, 1953 '2 Sheets-Sheet 2 t., N' M l f 1,

Patented einer. i5,

UNI-TED ,STATES issues BOILER AND WATER HEATER SYBTEM Thomas D. Casserly, Michigan City, Ind., assignor to Weil-McLain Company, Michigan a corporation of Delaware City; Inl,

Application January 80, 1933, Serial No. 654,159

4 Claims. (CL 122-32) for coal as the heating fuel in domestic boilers and while it has been obvious that the eilcient utilization of the heat units when` oil is used as the fuel, requires diilerent conditions than in the case of burning coal, nevertheless practically no eilorts have heretofore beenimade by manufacturers of domestic boilers toivchange their construction so as to adapt themi for more eillcient oil burning conditions.

Along with the increase in use of oil as a fuel,

has been a constantly growing demand for auto--Y matic hot water heaters. These have generally been independent of the house heating apparatus, using gas or separate oil burners, with consequent increase of investment andA maintenance.

In many cases also, gas may not be 'available and, in other cases, while the householder may be able to afford the installation of an oil burner with his boiler, he may not be able to afford the relatively high additional expense of a separate oil burning apparatus for a hot water heater.

One object of this invention, therefore, is to provide an improved boiler, particularly designed with reference to its repot and crown section as to promote the combustion eillciency of an oil burner utilized therewith and also to increase the eiliciency of the heat exchange between the products of combustion of the oil burner and the heat absorbing surfaces of the boiler.

Another object' of the invention is to provide a simple and economical hot water heater and oil burner heated boiler system such that the heater is maintained within a predetermined temperature range by the boiler water, the temperature of the water in the boiler in turn being automatically maintained by the oil burner of the boiler.

Other objectsof the invention will more clearly appear from vthe description and claims hereinafter following.

In the drawings forming a part of this srxiciiic cation, 'Figure l is a part side elevation, part vertical sectional view of a system showing the improvements incorporated therein, the boiler proper' being in elevation and the water heater in section. Figure 2 is a vertical, sectional view, upon a somewhat enlarged scale corresponding to the line 2-2 of Figure 1. Figure 3 is a vertical, sectional view corresponding to the line 3-3 of Figure 2. Figure 4 is a horizontal, sectional view corresponding to the line @,-e oi Figure 3. Figure 5 is a diagrammatic view illustrating the wiring diagram for` the automatically controlled apparatus employed Vin vthe system. And Figure 6 is a. sectional view illustrating a simple form of thermal check valve that may be employed.

In said drawings, the boiler is designated generally by the reference character A, and the hot water heater by the reierence character B.

The boiler chosen for illustration is of the domestic circular type with horizontally arranged sections and comprises an ash pit section 10; a ilrepot section 11; -a crown section 12; a plurality of intermediate sections lil-13; and a dome section 14. In the drawings, the full lines indicate the arrangement of the boiler as adapted for usinghot water. Whenthe heater is used as a steam boiler, the dome section 14 will be replaced by a steam dome section, in which, as will be understood by those skilled in the art, the water level will be maintained an appreciable distance below the top of the dome section 114. The return or cold water inlet is indicated at 15, the same connecting with the lower portion o! the flrepot section 11 and the riser or loutlet type for the hot water is indicated at 16. The otltake for the products of combustion to the chimney is indicated at 17, the same being provided with a suitable check damper 118, as customary. 'l

In carrying ,out the invention, the ash pit section 10 may be made o! any suitable form and size, they Jsame having an upper ledge 18 on which is supported the iirepot section 11. The repot section 11 is of special construction, par.- ticularly adapting it for'use in conjunction with an automatic oil burner. As shown, said section il comprises an outer water chamber wall 19, arranged in the form of an upwardly tapering cone. At one side, the section 11 is provided with the usual door opening 20 adapted to be closed by the door 21. At diametrically opposed points as best shown in Figure 3, the lirepot section 1i is provided on its interior at the top withenlargements or bulges 22 and, in line therewith onr the outer side o! the section, the

outer wall is carried up vertically as indicated at 23 and which outer portions 23 are likewise bulged or of semi-circular form, this construction being provided to provide nipple openings 24 to receive the nipples 25-25 forming the water connection with the crown section .12.

Particular attention is directed'to the formation oi the nrepot section v11. Heretofore, nre- 1pet sections of boilers oi the' general 'circular type and as adapted for coal burning, have possessed practically no or at best only a slight up'- ward taper and have necessarily been of relatively great height in order to support the necessary thickness of fuel bed and provide a chamber thereabove for combustion. In actualV practice, the ratio of the bottom diameter of ilrepot section to the height of the repot section has been approximately 3-2 and the taper, as above mentioned, has been practically negligible or at best only about 5 to the vertical. In the improved nrepot section as illustrated, the ratio of the bottom diameter of the section to height is .very much greater ythan heretofore and will preferably approximate the ratio of about 5-2. Furthermore, a very substantial taper or conical eifect is employed approximating an angle of 20 to the vertical. boiler is particularly adapted for oil burner. use. Referring to Figure 2, 26 indicates conventionally the delivery pipe from an oil burner `of the blower type, the same being entered as customary through the usual ash pit door opening 27, a perforatedplate 28 being substituted for the usual ash pit door. As customary, the ash pit section will preferably be lined with nre brick, as indicated at 29. With the products of combustion from the burning of oil as a fuel, delivered undergforced draft from the end of the pipe 26 into the ash pit section, the flames are obviously directed upwardly and in so doing will rbe compelled, in large part, to strike the inner inclined surfaces of the flrepot section' l1. These flames or products of combustion will in turn be more or less deflected inwardly and upl wardly by the surface of the nrepot section and Y directed in a more or less concentrated flame against the under surface of the crown section 12. In this connection, it will be observed that the distance traversed by the products of combustion from the point of delivery in the ash pit section to the point of striking the crown section is comparatively short so that all the surfaces of the ilrepot and crown sections deilning the fire-V pot 4chamber are impinged upon by the flames and products of combustion; while the latter are at their maximum temperature, thus effecting the most `eilicient transfer of heat from the flames and products of combustion to the water Jacket surfaces which contain the coolest portion of the water circulating within the boiler. Furthermore, because of the relatively reduced volume of the space in the flrepot chamber and the high temperature at which these surfaces are maintained, the eiliciency of combustion of the oil vapors is increased, it being well known that, the higher the temperature of the surrounding surfaces where combustion of oilrvapors takes place the more, efficient and complete the com; bustion will be. While the drawings illustrate conventionally the delivery or blower pipe of one common form oi oil burner, it will be understood that the advantages of the construction just described will be equally applicable where other types of oil burners are employed such as those mounted entirely within the ash pit section, such as oil burners of the so-called sprayer or whirlertype.

As will be understood., the number of intermediate sections 13 will vary in accordance with the'capacity of the boiler. Each of these sections is of circular horizontal slab type with suitable diametrical enlargements, as indicated at 30, to provide the necessary nipple openings, all of which are alined with the nipple openings be- With this construction, the` tween the crown section 12 and repot section, previously described. By reason of the partic- 'ular nipple connection between crown Vsection the adjacent sections are turned 180 relative .Y

tofeach other so that the vertical nue openings or passages 31-31 are staggered as indicated in Figure 1, thus providing for a back and forth travel of the products of combustion inpassing upwardly through the boiler and hence causing Va longer travel and corresponding increase in the interchange of heat units. Also, preferably, the under surface of each of the crown,V

intermediate, and dome sections are corrugated or made wavy, as indicated at 32-32, so as to expose a greater surface area to the products of combustion. 'I'he dome section 14 is provided with a circular passage or opening 33 corresponding to the circular flue pipe 17. Prefer-V ably, clean out doors 34--34 are provided up the front of the boiler, it being understood that the various sections will be suitably apertured therefor not only on the side which is disposed to the front of the boiler but at diametrically opposite points to permit of turning the various sections 180. Where said openings come to the rear of the boiler, the latter openings will be covered as by the plates 35-35. l

The boiler is preferably heat insulated by a suitable annular sheet metal casingv 36 and top cover 67 between which and the cast sections of the boiler will be interposed mineral wool yor other suitable heat insulating media 68. Y

Referring next to the hot water heater B, the same may be'of any suitable form but preferably comprises an inner cylindrical tank 37 to which the cold water is admitted through the pipe 38 and the heated water for household service withdrawn through the pipe 39. The hot water or storage tank 37 is in turn surrounded by an annular water heating tank 40 and the latter in turn surrounded by a layer of heat insulating material 41. The tanks are preferably supported above the floor level by any suitable means such as the platform 42 mounted on standards 43.

V'Ihe water heating tank 40 is placed in communication with the water circulating inthe with the n'repot section, as shown in Figures 1V and 3. With this arrangement,V itis evident that as the water is heated in the boiler A by the oil burner, the same will circulate to and through the heating tank 40 and back to the boiler,l thus heating the water stored within the inner tank 37.

Included in the return pipe connection 45 between the water heater and boiler is a thermostatically controlled check valve 46, indicated conventionally in Figure l, the same being of such construction and so arranged that when the water circulating therethrough to the boiler reaches a predetermined maximum temperature` the check valve flow and thereby stop circulation between the boiler and water heater. Said check valve may the thermal check valve will automatically shut off the -automatically start the oil burner 26.

is open to permit flow oi'the water from the right toward the left, as viewed in said figure, it

. will contact with the inner end of an adjustable set screw 149. As the temperature of the passing water rises and the element 148 is expanded. it is evident that the circulation will be restricted or entirely closed oil' since the valve 146 will be prevented from opening. The temperature at which the valve 146 may be entirely closed can be regulated by adjusting the screw 149, as apparent.

Also communicating with and responsive to the temperature of the water circulating through the boiler and heater is a thermostatv device indicated generally by the reference character C, the same in a hot water boiler being preferably tapped into the upper wall of the dome section 14. Said thermostat device C, which may be of any well known ionnsuch as now on the market, will be set to open and close an .electric switch or contact included in the wiring circuit 47-48. Said device will be set so as to control the maximum and minimum temperatures oi the water in the heating tank 40 and, preferably, will be Vset so as to open when the temperature reaches approximately 180 and close when the temperature falls to 170 so as to maintain the supplyor hot water at the desired temperature.

Referring now to Figure 5, the oil burner proper is there indicated conventionally by 'the reference character 26, and water circulating pump for the boiler at 50 and the usual room thermostat for the oil burner at 51. The thermostat device C is also indicated by the corresponding reference character.

When the demands on the boiler require the supply oi heat to the rooms oi' the house, the thermostat 51 will close in the usual manner, thus completing the circuit from the power line 52 through the wire 53, thermostat 51 through the circulating pump 50 (automatically electrically controlled), wire 54 to the usual motor of the oil burner 26 and from that motor by theA wire 55 back to the other mainline 56. A separate and independent circuit for stopping and starting the oil burner26 is eil'ected from the main line 52 through the wire 53, wire 47, thermostat device C, wire 48 to the motor of the oil burner 26 and back through the wire 55 to the other main line 56.

The operation of the complete system is 'as follows. When the temperature of the water in the boiler exceeds that required for heating the storage tank 37, circulation between the boiler and heater will be shut of! by the check valve 46, as previously. described. During the winter time when the boiler A is substantially constantly under demand andthe water therein is necessarily maintained hot, the thermostat. device C will preferably be cut out entirely. In

the summertime or during very moderate weather, however, the thermostat device'C will be operatively included in the circuit above described so that, independent of any room demand on the boiler A, when heat is required to raise the temperature'of the water in the supply tank 37, the thermostat device C will cut in and While the oil burner is thus operating to heat the water tank, the circulating pump 50 which vis employed in the usual manner to circulate the water through the pipe systems o! the house, will remain idle or inoperative inasmuch as the room thermostat 51 may be open during theseV conditions, and hence no surplus Vheat will be supplied to the rooms. When the temperature in the storage tank 37 has been raised kto the desired point, the thermostat device C will open, thus breaking the circuit' to the oil burner motor 26 and shut off the same. 1

From the foregoing description it win .be seen that the Vone oil burner is under automaticcontrol in the usual manner as regards supplying of heat to the rooms from the boiler A andis also under automatic control with respect to supplying heat to the water which in turn heats the hot water heater.. By reason of the check valve 46, excessive heating of the hot water tank is avoided at any time, mild or cold weather. A l

In the foregoing, the operation has been described with particular reference'to the boiler as adapted lforhot water heating. When .the boiler is employed for steam heating and a.l corresponding steam dome section substituted for the water dome section 14, the thermostat device C will then be tapped into the steam dome section at one side near the bottom thereof below the water level therein. The thermostat device will thus be responsive to the temperature of the water in the steam boiler rather than to"steam temperature, as will be understood. In

steam installation, the thermostat device will likewise be cut out when the boiler A is under constant demand'for room heating purposes but when the boiler B is not under such demand, asin the summertime, the water in the boiler will be heated only to such maximum temperature to which the thermostat device is set.

device cut out of service, it is evident that even though the water in the boiler is raised to the boiling point to generate steam, the water heaterl and pipe connections for circulating the boiler4 water through saidheating tank, said connections having included therein a thermostatic check valve constructed and arranged to prevent overheating of the heating tank.

2. In a boiler heater system, the combination with a boiler; of an automatically operable burner for heating said boiler: a water heater `having a hot water supply tank and a water heating tank therefor; pipe connections for circulating the boiler water through said heating Y tank; thermostatically controlled means included in the boiler-heating Itank circuit to limit the temperature to which the water in the tank heater is heated, and a thermostatically operable control device responsive to the temperature of the water in the boiler-heating tank circuit for controlling the automatically operable burner.

3. In a boiler heater system, the combination With the 'steam installation and the thermostat vwith a boiler; ot an automatically operable burner for heating said boiler; a'lwater heater having a hot water supply tank and aV water heating tank therefor; pipe connections for circulating the boiler water through said heating tank; a thermostatically operable control de vice Areaponsiveto the temperature ofthe water in the boiler-heating tank circuit for controlling tbe automatically operable burner; 4and a thermostatically controlled check valvein the pipe connection betweenthe boiler andy tank constx-med and arranged for shutting on circulation therebetween when the temperature oftlie water reaches a predetermined maximum.,r 4

4. In a boiler heater system, the combination with* a boiler; of a water heater having a storfige tank for the water to. be heated and a water heating tankrencircling the same; a pipe connection between the dome section of the boiler and the top of the water heating-tank; a pipe vconnection between the repot section o! the boiler and the bottom ot the water heating tank and having included. therein a thermostatically controlled check valve constructed and arranged vto,.prevent'overheatingof the heating. tank; an gautomaticalLv controlled 'heatingrunit i'or the boiler; and la device responsive tothe tempera- J otM the Waterain the dome section of the vtboiler Afor governing the operation of said heating THOMAS D. CASSERLY. l 

